Skiving machine



E. J. RAY

SKIVING MACHINE Sept. 4, 1934.

Filed May 10, 1933 Patented Sept. 4, 1934 UNITED STATES PATENT. OFFICE SKIVING MACHINE Eugene J. Ray, Beverly, Mass., assignor to United Shoe Machinery Corporation, Paterson, N. J.,. a corporation of New Jersey Application May 10, 1933, Serial No. 670,327

6 Claims. (C1. 699.5)

manner for producing a true circular cutting edge on the knife, .which mechanism may be substituted,;in machines of the above type, for existing mechanisms, without thenecesslt of otherwise changing or modifying such machines. Another object of the invention is to provide a grinding device which is normally held out of contact with the knife and which may be brought manually into grinding contact with a surface of the knife to true up and sharpen its cutting edge, when necessary, and which may be adjusted, prior thereto, to bring the operating face of the grinding wheel into alignment for such grinding contact.

Another object of the invention is to provide an improved grinding device in which the grinding wheel will be rotated by grinding contact with the knife and which may be utilized to hone or grind a surface on one side; of the cutting'edge of the knife after the other surface, which cooperates to form the cutting edge, has been beveled by another grinding mechanism.

With the above objects in view, the several features of the invention consist in certain novel features of construction, combinations, and arrangements of partahereinafter described and claimed, the advantages ofwhich will be obvious to those skilled inthe art, upon a consideration of the attached drawing .and the following description. Y i In the accompanying drawing, 7 Fig. 1 is a perspectiveview of a portion of a skiving machine showing a tubular skivingknife and the grinding attachment of the present invention; r

Fig. 2 is a horizontal sectional view of the grinding mechanism of the presentinvention, portions of such mechanism being shown in plan, and showing the relation of the mechanism to the skiving knife and its driving shaft and mount- Fig, 3 is a vertical section of the grinding wheel spindle bearingbracket; with the-spindle and wheel' shown in elevation in-normal 'position relatively'tothe skivingiknife, dash lines-ina knife holder 12 by an expanding clamping ring after grinding contact has been established by bodily movement ofthe Wheel; and

Fig. 4 is-a detail in side elevation, partly in section, showing a releasable stop which normally retains the grinding device out of grinding contact with theknife but which is releasable to .permit the removal of the device when necessary for changing the grinding wheel or for any other purpose. l v I i The present invention is illustrated as embodied in a skiving machine of the general'type disclosed in the United States patent to Alexander No.- 1,- 117,541, granted November 17, 1914,;t0 which-reference should be made fora complete description of the machine and its operation;

.The rotary tubular skiving knife of the machine is indicated by the reference numeral 10 and is .clearlyshown in Fig. 1, where the hinged portion of the casing, which covers and protects the'knife and other portions of the mechanism, has been removed in order that the present invention may be seen in relation to the machine. The knife is clamped against the cylindrical inside surface of 14 which is expanded by drawing a clamping plate 16 Within the knifelO by means of a clamping rod 18 and a rod 20 threaded into said rod 18.

mounted. This mounting of the'skiving knife is r fully illustrated and described in United States Letters Patent to Latham No. 1,342,120, granted June 1, 1 920, to which reference may be made for further details.

A beveled surface 26 is maintained on the outer surface of theknife l0 byaniexternal grindingwheel 30, shown diagrammatically inFig, land which may be brought into operation at the will of the, operator, as fully described in the abovementioned patent to Alexander.

The frame i0 of the machine, as it has. been :mai'iufactured for some years, has been provided with a semi-cylindrical boss 42 having a bore 44.- which is parallel to the axis of the knife shaft 24 and this bore has been utilized heretofore for sup- I porting-a grinding device of thetype' shown and described in- United States Letters-"Patent toLathe am; No. 1,266 ,027 dated'May .14.,"1918, upon-which the present invention is anairnprovementr Inorderto utilize. this bore in the" machine frame for dica ting the position of the wheel behind-the knife r the grinding device of the present invention, a bushing 50 is provided which may be clamped in the bore by a clamping screw 52. Referringpare ticularly to Fig. 2, this bushing has a bore 54, extending from one end to the other thereof, which bore is located in a horizontal plane but which is displaced from parallelism with the knife shaft 24 at a small angle indicated at A, this angle in practice being preferably about 2. In this bore is a stud 56 for supporting the improved grinding device of the present invention, this stud being urged to the left (in Fig. 2) by a yielding spring 58. On the outer end of the stud 56 is a transverse socket 60, the under side of which has a flat-. tened surface 62 for engagement with a surface 64 on an extension 65 of the bushing 50. The surfaces 62 and 64 cooperate to prevent the stud, and the hereinafter described grinding mechanism carried thereby, from turning about the axis of the stud but they permit movement of the same longitudinally. To limit this longitudinal movement, against the urge of the spring 58, a releasable stop is provided in the form of a flat spring 66 which is secured to the extension 65. -When the spring or stop 66 is depressed, the stud and its associated parts, i. e., the entire grinding device, may be removed from the machine.

Mounted for longitudinal adjustment in the socket 60 is the integral shank 70 of a bearing bracket 72. The shank 70 is provided with a reduced portion 74, the outer end of which is threaded at 76 and passes through a hole in the end of the socket. A yielding spring 78 is seated between this end of the socket 60 and the shoulder formed by the reduced portion of the shank. This spring forces the bracket toward the axis of the knife but such movement is prevented by a nurled adjusting nut 80 on the threaded portion '76 of the shank. This arrangement provides means for readily adjusting the shank longitudinally of the socket. Rotation of the shank in the socket is prevented by a studkey 82 which extends from the shank '70 and fits a slot 84 cut in the side of the socket 60. The bearing bracket '72 provides a mounting for a spindle 86 on which the grinding or honing wheel 88 is mounted. The grinding wheel is secured to the spindle by a nut 90 which forces the wheel against a collar 92 on the spindle. Seated in a recess in the bracket 72 is a ball thrust bearing 94 to take the end thrust that is transmitted to the collar 92 by the grinding wheel when it is being operated. A collar 96 is secured to the opposite end of the spindle 86 and prevents longitudinal movement of the spindle in the bearing bracket '72.

Before using the device of the present invention, the beveled edge 26 of the skiving knife 10 is ground by the grinding wheel 30, as described in the prior patents referred to herein. This grinding operation leaves a burr on the inside surface of the knife and the purpose of the present device is to remove this burr and to grind the inside cylindrical surface of the knife 10 on a slight bevel so as to produce a true and sharp circular cutting edge that is concentric with the knife shaft 24 and which lies in a plane exactly perpendicular to said" shaft; An additional advantage of this procedure is that the cutting edge of the knife is inside surface of the knife in the above manner will now be described.

The operator presses against the socket 60 which causes a movement'of the bearing bracket 72 and the grinding wheel 88 toward the knife, the spring 54 yielding to permit such movement. When first put into use, the grinding wheel 88 is adjusted, by means of the nurled adjusting nut 80, so that, as this movement is continued, the wheel 88 will clear the inside surface of the knife. The nut 80 is then adjusted slowly as the socket 60 is-moved in and out until suitable grinding contact has been made with the revolving knife and the inside surface of the knife has been ground around its entire circumference to produce the slight bevel at the angle A with the inside cylindrical surface of the knife. When the knife has been suificiently ground or honed, the transverse socket 60 is released and it is returned by the spring 54 to inoperative position, with the socket in contact with the stop spring 66. The grinding wheel 88 is nowclear of the knife and will not interfere with it while the usual skiving operations are being performed. When the knife again becomes dull, the bevel 26 is ground by the grinding into contact with the knife, after the'nut 80-has been adjusted slightly to suitably re-position the grinding wheel for grinding contact with the knife;

It is only necessary to depress the stop spring 66 slightly and the entire device may be completely removed from the machine. This is only necessary when the grinding wheel is to be changed or adjusted, or when it may interfere with certain special types of work. 1

Having thus described my invention, what I claim as new and desire to secure by Letters Patent of the United States is:' r a 1. A skiving machine having, in combination, a skiving knife, a grinding wheel, a spindle supporting the wheel with its peripheral face in position to be brought manually into grinding contact with one surface of the knife, means normally tending to move said face out of contact with said surface, and adjustable means for aligning said face and contact.

2. A skiving machine having, in combination, a tubular skiving knife, a drivingshaft for the knife, a spindle, a grinding wheel mounted on the spindle, and means for guiding the grinding wheel in a path at a slight angle to the shaft'to bring its peripheral face into and out of grinding contact with a surface of the knife.

3. A skiving machine having, in combination, a tubular skiving knife, a driving shaft for the knife, a spindle, a grinding wheel mounted on the spindle, adjustable means for aligning the peripheral face of the wheel for grinding contact with a surface of the knife, and means for guiding the grinding wheel in a path at a slight angle to the shaft'to bring said face into and out of grinding contact with said surface of the knife.

4. A skiving machine having, in combination, a tubular skiving knife, a grinding wheel having its peripheral face arranged to be brought into grinding contact with the inner surface of the knife, and means for supporting the grinding wheel with its axis of rotation inclined at a substantial angle to the plane of the knife edge.

5. A skiving machine having, in combination, a tubular skiving knife, a driving shaft for the knife, a spindle, a grinding wheel mounted on the spindle, means for supporting the grinding wheel with its axis of rotation inclined at a substantial angle to the plane of the knife edge, and

means for guiding the grinding wheel in a path said surface for grinding H I mounted in said bearing bracket, a grinding wheel on said spindle and positioned so that its peripheral face will engage a surface of the knife at a substantial angle upon manual sliding of the stud in the frame, spring means to move the wheel out of engagement with said surface, a stop to limit such movement of the wheel, and an adjustablestop to limit the movement of said shank in said socket and thereby accurately align said face and said surface for grinding contact.

EUGENE J. RAY. 

